Istanbul

Istanbul is two continents and a ferry ride, with tea on deck and gulls following the boat.

Hagia Sophia has been a church, a mosque, a museum and a mosque again, and almost everyone who passed through left a trace. In the upper gallery, a Viking carved his name into the marble balustrade over a thousand years ago. It still reads Halfdan.

Trevlo's audio tour of Hagia Sophia tells its story under the dome, from emperors to sultans. Go at your own pace, then cross the water. Your first tour is free.